This study was carried out to disclose the effect of beny thinning and
trunk girdling treatments solely or in combination (for improving bunch and
berry quality) on the date of harvest. yield, bunch and berry characteristics
and vegetative growth of Black Monukka grapevines. Twelve conducted
treatments were applied as follows: untreated vines (control), berry thinning
(1) (Retention of five shoulders at the base of the bunch with the alternative
removal of the branches and removing the terminal quarter of the bunch at 2-
3 mm berry diameter) (Bl). berry thinning (2) (The same technique described
above berry thinning (1) with the removed portion being increased as to be
half of the bunch) (Ba), girdling (1) after fruit set (by removing a narrow ring of
the bark (2—3mm entirely around the trunk) (G1) and girdling (2) at veraison
stage (G2).
The results showed that all conducted treatments were effective in
increasing average bunch weight and yieldivine except all (3;) treatments.
Girdling after fruit sat alone or in combination with all berry thinning
treatments improved physical characteristics of bunches and berries. girdling
(2) at veraison stage alone or in combination with all berry thinning
treatments increased T8896 of berry juice. TSSlacid ratio, improved berry
colouration, while decreased acidity% of berry juice). Combination treatments
of thinning, girdling (1) and girdling (2)) had the highest values of
morphological and chemical estimates of vegetative growth compared with
control. The obtained results revealed the superiority of Berry thinning (1) +
Girdling (1) + Girdling (2) treatment owing to its positive effect on most of the
studied characters.